Chemicals and the synthesizing methods thereof

ABSTRACT

A series of ladder-type multifused arenes (hexacyclic, heptacyclic and nonacyclic units) and the synthesizing methods thereof are provided. The ladder-type multifused arenes are copolymerized with various electron-deficient acceptor units to afford various p-type low-band gap conjugated copolymers.

The application claims the benefit of Taiwan Patent Application No.101107975, filed on Mar. 8, 2012, in the Taiwan Intellectual PropertyOffice, the disclosures of which are incorporated by reference as iffully set forth herein.

FIELD OF THE INVENTION

The present invention relates to a polymer monomer and the polymersthereof, and the synthetic method of the monomer and the polymers,wherein the polymers can serve as an active layer material of an organicpolymer solar cell.

BACKGROUND OF THE INVENTION

In order to achieve the goal of the high efficiency organic polymersolar cell, it is a key point to use a good p-type conjugated polymersemiconductor material. Usually, the p-type conjugated polymer appliedto the organic polymer solar cell should have the followingproperties: 1) a low-band gap (smaller than 1.7 eV) for having a strongand broad absorption spectrum to the scopes of the red light or theinfrared ray in order to utilize the sunlight completely, 2) a highelectron hole mobility (larger than 10⁻³ cm²V⁻¹S⁻¹) for increasing thethickness of the active layer to strengthen the light collection anddecreasing the serial resistors at the same time, and thus preventingfrom the electron hole recombination, 3) a high solubility forsatisfying the demands of solvent wet process, and 4) a lower energylevel (highest occupied molecular orbital, HOMO) for achieving a higheropen circuit voltage, and the lowest unoccupied molecular orbital (LOMO)energy level must at least higher than the LUMO 0.3V of the n-typesemiconductor material for forming the electron transition potential tofacilitate the exciton separation.

SUMMARY OF THE INVENTION

The present invention relates to the chemical structures of theladder-type multifused multi-electron donor materials and the syntheticmethod thereof, and to the p-type low-band gap conjugated polymer formedof the ladder-type multifused multi-electron donors and anelectron-deficient acceptor, the synthetic method thereof and theapplication thereof in the field of the organic polymer solar cell.

In order to achieve the above purposes, the present invention provides apolymer, having a structure being one selected from a group consistingof:

wherein A is an electron-deficient monomer, n is an integer larger than2 and R is a side chain at least including a carbon atom.

In order to achieve the above purposes, the present invention alsoprovides a polymer monomer having a structure being one selected from agroup consisting of:

wherein R is a side chain at least including a carbon atom.

In order to achieve the above purposes, the present invention furtherprovides a method of synthesizing a monomer, including steps ofproviding a compound having a structure being one of

wherein R is a side chain at least including a carbon atom, andperforming an annulation with the compound to cause the compound to formthe monomer.

Other objects, advantages and efficacies of the present invention willbe described in detail below taken from the preferred embodiments withreference to the accompanying drawings, in which:

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The products and method of the present invention will be fullyunderstood from the following embodiments and thereby being accomplishedbased thereon by one skilled in the art. However, the practice of thepresent application is not intended to limit to the followingembodiments in its practice, and the skilled person can still conductother embodiments according to the spirit of embodiments presentedherein that belong to the scope of this invention.

The synthetic processes of the heptacyclic multielectron monomer Sn-DTBCare provided as follows.

The Synthesis of the Compound 2:

The compound 1 (6.0 g, 43.4 mmol) is placed in a 250 mL double-neckedflask under vacuum and to be baked therein for three times, 60 mLanhydrous tetrahydrofuran is added thereinto, and then the lithiumdiisopropylamide (2.0 M, 23.9 mL, 47.8 mmol) is slowly dropped thereintounder 0° C. for reacting for 1 hr. The mixture is returned to the roomtemperature after adding 1-bromooctane (8.8 g, 45.6 mmol), and beingheated under 60° C. at reflux for 12 hrs. The reaction is terminated byadding water, and the organic solvent is removed under lowered pressure.The organic layer is collected by extracting with ether (50 mL×3) andpure water (50 mL), and the collected organic layer is dried overmagnesium sulfate (MgSO₄). After removal of the organic solvent againunder lowered pressure, the residue is removed by lowered pressuredistillation at 150° C. Finally, the residue is purified by columnchromatography on silica gel (using hexane as eluent) to give acolorless liquid 2 (2.7 g, 25%). ¹H NMR (CDCl₃, 300 MHz, ppm): (t, J=6.6Hz, 6H), 1.27-1.38 (m, 20H), 1.45-1.49 (m, 4H), 2.13 (t, J=6.9 Hz, 4H).

The Synthesis of the Compound 3:

The compound 2 (2.5 g, 9.98 mmol) and bis(pinacolato)diboron (2.3 g,9.07 mmol) are placed in a 100 mL double-necked flask, and the Pt(PPh₃)₄(339 mg, 0.27 mmol) is added into the double-necked flask in a glovebox. After transferring the double-necked flask outside the glove box,40 mL of DMF is added into the flask under nitrogen. After heating thestirring the mixture at 80° C. for 24 hrs, the organic layer iscollected by extracting with ether (200 mL×3) and pure water (100 mL),the collected organic layer is dried over MgSO₄, and the organic solventis removed under lowered pressure. Finally, the residue is purified bycolumn chromatography on silica gel (ethyl acetate/hexane v/v=1/25 aseluent) to give a colorless liquid 3 (3.77 g, 75%). ¹H NMR (CDCl₃, 300MHz, ppm): (m, 6H), 1.21-1.31 (m, 48H), 2.16 (t, J=7.5 Hz, 4H).

The Synthesis of the DTBC Compound

The compound 3 (0.701 g, 1.39 mmol), the compound 4 (0.513 g, 0.579mmol) and K₂CO₃ (0.96 g, 6.952 mmol) are placed in a 100 mLdouble-necked flask, and the Pd(PPh₃)₄ (67 mg, 0.058 mmol) is added intothe double-necked flask in a glove box. After transferring thedouble-necked flask outside the glove box, 25 mL tetrahydrofuranpre-degassed with nitrogen and 1.2 mL pure water are added into theflask under nitrogen. After heating the mixture at 65° C. at reflux for48 hrs, the organic solvent is removed therefrom under lowered pressure.The organic layer is collected by extracting with ether (100 mL×3) andpure water (150 mL), and the collected organic layer is dried overmagnesium sulfate (MgSO₄). After removal of the organic solvent underlowered pressure, the residue is purified by column chromatography onsilica gel (using hexane as eluent) to give a yellow sticky DTBC (0.312g, 51%). ¹H NMR (CDCl₃, 300 MHz, ppm): δ 0.73 (t, J=6.6 Hz, 6H), 0.90(t, J=6.9 Hz, 12H), 1.08 (br, 18H), 1.22-1.52 (m, 42H), 1.64-1.78 (m,8H), 1.82-1.94 (m, 4H), 1.98-2.06 (m, 2H), 2.48-2.58 (m, 2H), 3.12 (t,J=7.8 Hz, 4H), 3.33 (t, J=7.8 Hz, 4H), 4.70-4.80 (m, 1H), 7.50 (d, J=5.4Hz, 2H), 7.56 (d, J=5.4 Hz, 2H), 7.87 (br, 1H), 8.06 (br, 1H), 8.89 (br,2H).

The Synthesis of Sn-DTBC Compound

The DTBC (315.6 g, 0.296 mmol) is placed in a 100 mL double-necked flaskunder vacuum and to be baked therein for three times, 20 mL anhydroustetrahydrofuran is added thereinto, and then the tert-butyllithium(t-BuLi, 1.6 M, 0.74 mL, 1.184 mmol) is slowly dropped thereinto under−78° C. (by mixing the aetone and the liquid nitrogen) for reacting for1 hr. The chlorotrimethylstannane (1.0 M, 2.4 mL, 2.4 mmol) is addedinto the mixture under −78° C., and the mixture is returned to the roomtemperature for reacting 15 hrs. The reaction is terminated by addingwater, and the organic solvent is removed under lowered pressure. Theorganic layer is collected by extracting with ether (50 mL×3) and purewater (50 mL), and the collected organic layer is dried over magnesiumsulfate (MgSO₄). After removal of the organic solvent under loweredpressure, a yellow sticky Sn-DTBC is obtained (405.7 mg, 98.5%). ¹H NMR(CDCl₃, 300 MHz, ppm): 0.51 (s, 18H), 0.75 (t, J=6.6 Hz, 6H), 0.92 (t,J=6.3 Hz, 12H), 1.05-1.20 (m, 18H), 1.22-1.50 (m, 42H), 1.64-1.77 (m,8H), 1.82-1.99 (m, 4H), 1.99-2.05 (m, 2H), 2.55-2.61 (m, 2H), 3.15 (t,J=7.8 Hz, 4H), 3.33 (t, J=7.5 Hz, 4H), 4.70-4.80 (m, 1H), 7.61 (s, 2H),7.92 (br, 1H), 8.10 (br, 1H), 8.89 (br, 2H).

The synthetic processes of the polymer PDTBCDTBT are provided asfollows.

The Sn-DTBC (306 mg, 0.220 mmol), the compound 5 (100.7 mg, 0.220 mmol),tris(dibenzylideneacetone)dipalladium (10.1 mg, 0.011 mmol) andtri(2-methylphenyl)phosphine (26.8 mg, 0.088 mmol) are placed in a 50 mLsingle-necked flask, and 7.5 mL of chlorobenzene pre-degassed withnitrogen is added into the flask. The mixture is degassed with nitrogenfor 10 min, and the flask is equipped with a reflux condensor and thenbeing moved into a focused microwave synthesizer for microwavepolymerization under a condition of 270 watt at 180° C. for 50 min. Inturn, the end-capping 2-(tributylstannyl)thiophene (41.0 mg, 0.110 mmol)is added into the mixture for microwave polymerization under 270 watt at180° C. for 10 min, and 2-bromothiophene (19.7 mg, 0.121 mmol) is addedthereinto for reacting under the same condition. Then, 200 mL methanolis used for re-precipitation and the solid is collected by gravityfiltration. After the solid is continuously extracting with the acetonefor one day, it is continuously extracting with 4:1hexane/tetrahydrofuran for two days. The solid is resolved in the hottoluene, and 5 eq. of Si-Thiol (47.5 mg, 0.055 mmol) and a magneticstirrer are added for demetalization for 12 hr. After the Si-Thiol isfiltered by gravity, the organic solvent is removed under loweredpressure and the residue is re-recipitated by methanol. Afterfiltration, the PDTBCDTBT as a black green solid is obtained (159 mg,53%).

The synthetic processes of the polymers PDTSCBT and PDTPCBT are providedas follows.

The Br-DTBC (0.43 g, 0.389 mmol), the compound 6(4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzo[c][1,2,5]thiadiazole,0.151 g, 0.389 mmol), tris(dibenzylideneacetone)dipalladium (14.2 mg,0.016 mmol), tri(2-methylphenyl)phosphine (37.9 mg, 0.125 mmol) and thesurfactant (Alivant 336, two drop) are placed in a 100 mL double-neckedflask, and 24 mL toluene pre-degassed with nitrogen/1.0M sodiumbicarbonate (5:1) are added into the flask. The mixture is degassed withnitrogen for 10 min, and the mixture is heated at 90° C. at reflux undernitrogen. After 30 min, the solution is dropped into 200 mLmethanol/pure water (3:1) for reprecipitation and the solid is collectedby gravity filtration. The solid is continuously extracting with theacetone for one day, continuously extracting with hexane for one day,and continuously extracting with tetrahydrofuran for two days. The solidis resolved in the hot dichlorobenzene, and 5 eq. of Si-Thiol (69.2 mg,0.08 mmol) and a magnetic stirrer are added for demetalization for 12hr. After the Si-Thiol is filtered by gravity, the residue isre-recipitated by methanol. After filtration, the PDTSCBT as a blacksolid is obtained (240 mg, 57%).

Synthesis of the PDTPCBT Polymer

The Sn-DTPC (400 mg, 0.349 mmol), the compound 7(4,7-dibromo-2,1,3-benzothiadiazole, 103 mg, 0.349 mmol),tris(dibenzylideneacetone)dipalladium (12.8 mg, 0.014 mmol) andtri(2-methylphenyl)phosphine (34.0 mg, 0.112 mmol) are placed in a 50 mLsingle-necked flask, and 10 mL chlorobenzene pre-degassed with nitrogenis added into the flask. The mixture is degassed with nitrogen for 10min, and the flask is equipped with a reflux condensor and then beingmoved into a focused microwave synthesizer for microwave polymerizationunder a condition of 270 watt at 180° C. for 50 min. In turn, theend-capping 2-(tributylstannyl)thiophene (65 mg, 0.175 mmol) is addedinto the mixture for microwave polymerization under 270 watt at 180° C.for 10 min, and 2-bromothiophene (31 mg, 0.188 mmol) is added thereintofor reacting under the same condition. Then, 200 mL methanol is used forre-precipitation and the solid is collected by gravity filtration. Afterthe solid is continuously extracting with the acetone for one day, it iscontinuously extracting with hexane for one day. The solid is resolvedin the tetrahtdrofuran, and 5 eq. of Si-Thiol (60.5 mg, 0.07 mmol) and amagnetic stirrer are added for demetalization for 12 hr. After theSi-Thiol is filtered by gravity, the residue is re-recipitated bymethanol. After filtration, the PDTPCBT as a black solid is obtained(180 mg, 54%). Mn=36.4 kDa, PDI=1.21 • ¹H NMR (CDCl₃, 300 MHz, ppm):0.71-1.55 (m, 54H), 2.01 (br, 8H), 2.51 (br, 2H), 4.25 (br, 4H), 4.68(br, 1H), 7.05 (br, 2H), 7.38-7.51 (br, 4H), 8.31 (br, 2H).

The synthetic processes of the heptacyclic multielectron monomer Br-DTCFare provided as follows.

Synthesis of the Compound 9

The compound 8 (3.62 g, 5.18 mmol) is placed in a 250 mL double-neckedflask and the flask is then equipped with the reflux condenser and thesleeve stopper. After dissolving the compound 8 in 150 mL ethanol, thesodium hydroxide (2.90 g, 72.5 mmol) and the distilled water (30 mL) areadded into the solution for being heating under 90° C. at reflux for 12hr. The mixture is cooled to the room temperature, the ethanol isremoved by a rotary evaporator, and 1M hydrochloric acid is added to theresidue under ice bath until the mixture is acid. After suctionfiltration, a white solid (2.77 g, 83%) is collected. ¹H-NMR (300 MHz,CDCl₃, δ ppm): 1.85-1.79 (m, 4H), 1.16-0.72 (m, 30H), 7.25 (d, J=5.4 Hz,2H), 7.36 (s, 1H), 7.41 (d, J=7.8 Hz, 2H), 7.61 (d, J=5.4 Hz, 2H), 7.66(d, J=7.8 Hz, 2H).

Synthesis of the Compound 11

The compound 9 (4.28 g, 6.66 mmol) is placed in a 250 mL double-neckedflask and the flask is then equipped with the one-way valve and thesleeve stopper for being baked under vacuum. 100 mL anhydrousdichloromethane is added into the flask, the oxalyl dichloride (3.38 g,26.63 mmol) is dropped into the flask and 1 mL N,N-dimethylformide (DMF)(1 v %) is slowly dropped into the flask for incubating 12 hr at roomtemperature. The liquid is removed under lowered pressure to obtain ayellow solid. This solid is dissolved in 70 mL anhydrousdichloromethane, the additional aluminum chloride (2.34 g, 17.55 mmol)is placed into a 500 mL double-nacked flask for being baked undervacuum, and then 400 mL anhydrous dichloromethane is added thereinto.The above solution is sucked by a syringe under the ice bath at 0° C.and being dropped into a 250 mL double-nacked flask, and the solutionchanges from pale yellow to orange and then reveals black in 3 hr underroom temperature. The reaction is terminated by adding 10 mL cold 1Mhydrochloric acid, and the dichloromethane is removed by filtrationunder lowered pressure. The residue is extracted with ethyl acetate andsaline (×3) and additional sodium bicarbonate solution, and dried overMgSO₄. The residue is purified by column chromatography on silica gel(using 1:25 (v/v) ethyl acetate/hexane as eluent) to give a red orangesolid (2.14 g, 53%). ¹H-NMR (300 MHz, CDCl₃, δ ppm): 1.19-0.66 (m, 30H),2.02-1.97 (m, 4H), 7.08 (s, 2H), 7.15 (d, J=4.8 Hz, 2H), 7.19 (d, J=4.8Hz, 2H), 7.75 (s, 2H).

Synthesis of the Compound 12

A mixture of the compound 11 (1.02 g, 1.68 mmol) and potassium hydroxide(1.84 g, 32.86 mmol) is placed in a 100 mL double-necked flask and theflask is then equipped with the reflux condenser and the sleeve stopper.The mixture is dissolved by adding 50 mL diethylene glycol, andhydrazine (1.65 g, 32.86 mmol) is slowly dropped thereinto after thesolution is heated to 90° C. The solution is black when it is heated to180° C. and being incubated for 24 hr. Return to the room temperature,the solution is extracted with ether and saline (×3) and the organiclayer is collected and dried over MgSO₄. The residue is purified bycolumn chromatography on silica gel (using hexane as eluent) to give abeige solid (0.16 g, 16%). ¹H-NMR (300 MHz, CDCl₃, δ ppm) 1.27-0.67 (m,30H), 2.07-2.02 (m, 4H), 3.75 (s, 4H), 7.13 (d, J=5.1 Hz, 2H), 7.31 (d,J=5.1 Hz, 2H), 7.42 (s, 2H), 7.77 (s, 2H).

Synthesis of the Compound DTCF

The compound 12 (0.3 g, 0.52 mmol) is placed in a 100 mL double-neckedflask and the flask is then equipped with the reflux condenser and thesleeve stopper for being baked under vacuum. 20 mL anhydrous dimethylsulfoxide (DMSO) is added into the flask under nitrogen. Sodiumt-butoxide (0.3 g, 3.12 mmol) dissolved in 15 mL anhydrous DMSO isplaced into another 100 mL double-necked flask equipped with a one-wayvalve and the sleeve stopper, which is sucked by a syringe at 80° C. andslowly dropped into the above-mentioned double-necked flask to make thesolution changes from pale yellow to black brown. After incubating forone hour, 1-bromooctane (0.6 g, 3.10 mmol) is slowly dropped into theflask and the flask is heated to 90° C. for 4 hr. After cooling to theroom temperature, the reaction is terminated by slowly adding 10 mLdistilled water, the mixture is extracted with ether and saline (×3) anddried over MgSO₄. After the residue is concentrated under loweredpressure, it is purified by column chromatography on silica gel (usinghexane as eluent) to give a yellowish-brown sticky liquid (0.45 g, 85%).¹H-NMR (300 MHz, CDCl₃, δ ppm): 1.28-0.67 (m, 90H), 2.05-1.86 (m, 12H),6.99 (d, J=4.8, 2H), 7.27 (d, J=4.8, 2H), 7.31 (s, 2H), 7.57 (s, 2H).

Synthesis of the Compound Br-DTCF

The compound DTCF (0.45 g, 0.44 mmol) is placed into a 50 mLsingle-necked flask, and 20 mL of CHCl₃ is added into the flask fordissolving the compound. After slowly adding the NBS (0.17 g, 0.96mmol), the mixture is incubated at room temperature for 12 hr. Then, theCHCl₃ is removed by concentrated under lowered pressure, and the residueis extracted with ether and saline (×3) and dried over MgSO₄. Theresidue is purified by column chromatography on silica gel (using hexaneas eluent) to give a pale yellow solid (0.45 g, 87%). ¹H-NMR (300 MHz,CDCl₃, δ ppm): 1.27-0.64 (m, 90H), 1.99-1.86 (m, 12H), 7.00 (s, 2H),7.23 (s, 2H), 7.54 (s, 2H).

The synthetic processes of the polymer PDTCFBT are provided as follows.

A mixture of Br-DTCF (150 mg, 0.127 mmol), the compound 6 (49.1 mg,0.127 mmol), Pd₂(dba)₃ (4.6 mg, 0.005 mmol), P(o-tolyl)₃ (12.32 mg, 0.04mmol) and a drop of Aliquat 336 is placed in a 20 mL seal tube and 1Msodium bicarbonate solution is prepared. 5.4 mL of 1:5 (v/v) toluene/1Msodium bicarbonate solution is added into the solution and degassed bynitrogen for 10 min. After heating the reaction under 90° C. for 72 hr,one drop of bromobenzene is added into the reaction for continuouslyheating the reaction for 12 hr, and one more drop of4,4,5,5-tetramethyl-2-phenyl-1,3,2-dioxaborolane is added thereinto forreacting for 12 hr. The above solution is slowly dropped into themethanol, the solid is collected by gravity filtration and washed by themethanol and the distilled water for three times to remove the salt, andthe soxhlet extraction is carried out in turn by acetone and hexane.Then, the remaining solid is collected and dissolved in THF and added byPd-thio gel (Silicycle Inc.) for removing the Pd catalyst for 12 hr. Theresulting solution is concentrated under lowered pressure for removingTHF and being dropped into the methanol for re-precipitation. Thepolymer PDTCFBT as a blue black solid is collected by gravity filtration(87 mg, 56%). ¹H-NMR (300 MHz, CDCl₃, δ ppm): 0.70-1.36 (br, 90H),1.93-2.20 (br, 12H), 7.35 (br, 2H), 7.54-7.57 (br, 2H), 7.85-7.90 (br,2H), 8.04 (br, 2H). Mn=33054 g/mol, Mw=94733 g/mol, PDI=2.87.

The synthetic processes of the polymers PBBCPDTTPD, PBBCPDTBT andPBBCPDTBT-F are provided as follows.

The Synthesis of the Polymer PBBCPDTTP

The Sn-BBCPDT (180 mg, 0.118 mmol), the compound 13(thieno[3,4-c]pyrrole-4,6-dione, 50.0 mg, 0.118 mmol),tris(dibenzylideneacetone)dipalladium (4.3 mg, 0.005 mmol) andtri(2-methylphenyl)phosphine (11.5 mg, 0.04 mmol) are placed in a 50 mLsingle-necked flask, and 7 mL of chlorobenzene pre-degassed withnitrogen is added into the flask. The mixture is degassed with nitrogenfor 10 min, and the flask is equipped with a reflux condenser and thenbeing moved into a focused microwave synthesizer for microwavepolymerization under a condition of 270 watt at 180° C. for 50 min. Inturn, the end-capping 2-(tributylstannyl)thiophene (22.3 mg, 0.06 mmol)is added into the mixture for microwave polymerization under 270 watt at180° C. for 10 min, and 2-bromothiophene (9.6 mg, 0.064 mmol) is addedthereinto for reacting under the same condition. Then, 200 mL methanolis used for re-precipitation and the solid is collected by gravityfiltration. After the solid is continuously extracting with the acetonefor one day, it is continuously extracting with hexane for one day. Thesolid is resolved in the tetrahydrofuran, and 5 eq. of Si-Thiol (21.6mg, 0.025 mmol) and a magnetic stirrer are added for demetalization for12 hr. After the Si-Thiol is filtered by gravity, the residue isre-recipitated by methanol. After filtration, the polymer PBBPDTTPD as adark purplish red solid is obtained (140 mg, 81%). Mn=24.5 kDa,PDI=3.06.

Synthesis of Polymer PBBCPDTBT

The Sn-BBCPDT (200 mg, 0.131 mmol), the compound 7(2,1,3-benzothiadiazole, 38.6 mg, 0.131 mmol),tris(dibenzylideneacetone)dipalladium (4.8 mg, 0.005 mmol) andtri(2-methylphenyl)phosphine (12.7 mg, 0.05 mmol) are placed in a 50 mLsingle-necked flask, and 8 mL of chlorobenzene pre-degassed withnitrogen is added into the flask. The mixture is degassed with nitrogenfor 10 min, and the flask is equipped with a reflux condensor and thenbeing moved into a focused microwave synthesizer for microwavepolymerization under a condition of 270 watt at 180° C. for 50 min. Inturn, the end-capping 2-(tributylstannyl)thiophene (24.7 mg, 0.065 mmol)is added into the mixture for microwave polymerization under 270 watt at180° C. for 10 min, and 2-bromothiophene (11.5 mg, 0.07 mmol) is addedthereinto for reacting under the same condition. Then, 200 mL methanolis used for re-precipitation and the solid is collected by gravityfiltration. After the solid is continuously extracting with the acetonefor one day, it is continuously extracting with hexane for one day. Thesolid is resolved in the tetrahydrofuran, and 4 eq. of Si-Thiol (18 mg,0.021 mmol) and a magnetic stirrer are added for demetalization for 12hr. After the Si-Thiol is filtered by gravity, the residue isre-recipitated by methanol. After filtration, the polymer PBBCPDTBT as ablackish green solid is obtained (134 mg, 69%). Mn=9.3 kDa, PDI=1.78.

Synthesis of the Polymer PBBCPDTBT-F

The Sn-BBCPDT (163 mg, 0.107 mmol), the compound 14(5,6-difluoro-2,1,3-benzothiadiazole, 45.4 mg, 0.107 mmol),tris(dibenzylideneacetone)dipalladium (3.9 mg, 0.004 mmol) andtri(2-methylphenyl)phosphine (10.4 mg, 0.03 mmol) are placed in a 50 mLsingle-necked flask, and 6 mL of chlorobenzene pre-degassed withnitrogen is added into the flask. The mixture is degassed with nitrogenfor 10 min, and the flask is equipped with a reflux condensor and thenbeing moved into a focused microwave synthesizer for microwavepolymerization under a condition of 270 watt at 180° C. for 50 min. Inturn, the end-capping 2-(tributylstannyl)thiophene (20.2 mg, 0.058 mmol)is added into the mixture for microwave polymerization under 270 watt at180° C. for 10 min, and 2-bromothiophene (9.4 mg, 0.076 mmol) is addedthereinto for reacting under the same condition. Then, 200 mL methanolis used for re-precipitation and the solid is collected by gravityfiltration. After the solid is continuously extracting with the acetonefor one day, it is continuously extracting with hexane for one day. Thesolid is resolved in the tetrahydrofuran, and 4 eq. of Si-Thiol (18 mg,0.021 mmol) and a magnetic stirrer are added for demetalization for 12hr. After the Si-Thiol is filtered by gravity, the residue isre-recipitated by methanol. After filtration, the polymer PBBCPDTBT-F asa blackish green solid is obtained (120 mg, 69%). Mn=49.9 kDa, PDI=1.48.

The synthetic processes of the heptacyclic multielectron monomer Sn-IDTTare provided as follows.

Synthesis of the Compound 17

The compound 15 (diethyl 2,5-Dibromoterephthate, 6.05 g, 15.9 mmol) andthe compound 16 (2-(tributylstannyl)thieno[3,2-b]thiophene, 15.71 g,36.6 mmol) are placed in a 250 mL double-necked flask, and the Pd(PPh₃)₄(0.74 g, 0.64 mmol) is added into the double-necked flask in a glovebox. After transferring the double-necked flask outside the glove box,78 mL of toluene pre-degassed by nitrogen is added into the flask. Underthe nitrogen, the mixture is heated under 130° C. at reflux for 16 hrs,the organic layer is collected by extracting with ether (100 mL×3) andpure water (150 mL), the collected organic layer is dried over MgSO₄,and the organic solvent is removed under lowered pressure. Finally, theresidue is purified by column chromatography on silica gel (ethylacetate/hexane v/v=1/20 as eluent) to give a golden solid 17 (6.9 g,87%). ¹H NMR (CDCl₃, 300 MHz, ppm): (t, J=6.9 Hz, 6H), 4.21-4.28 (q,J=7.2 Hz, 4H), 7.28 (m, 4H), 7.40 (d, J=5.1 Hz, 2H), 7.88 (s, 2H).

Synthesis of the Compound 18

1.0 M Grignard Reagent Preparation:

The magnesium powder (3.2 g, 132.0 mmol) is placed in a 250 mLdouble-necked flask to be baked under vacuum for three times, 120 mLanhydrous tetrahydrofuran, 1-bromo-4-(octyloxy)benzene (34.23 g, 120mmol) and a drop of 1,2-dibromoethane are added thereinto, and themixture is incubated for 1 hr after being slightly heated. The compound17 (4.8 g, 9.6 mmol) is placed in a 250 mL double-necked flask to bebaked under vacuum for three times, 50 mL anhydrous tetrahydrofuran isadded thereinto under nitrogen, and 76.8 mL of freshly prepared Grignardreagent is added into this flask for being heated under 80° C. at refluxfor 16 hrs. The mixture is extracted with 150 mL of ammonium chloride,150 mL of ether (×2) and 100 mL of pure water, and the organic layer iscollected and dried over MgSO₄. The organic solvent is removed bylowered pressure, and the residue is purified by column chromatographyon silica gel (ethyl acetate/hexane v/v=1/10 as eluent) to give a paleyellow solid 18 (5.17 g, 44%). ¹H NMR (CDCl₃, 300 MHz, ppm): 0.86-0.90,(t, J=7.2 Hz, 6H), 1.28-1.45 (m, 20H), 1.75-1.80 (m, 4H), 3.42 (s, 2H),3.94 (t, J=6.6 Hz, 4H), 6.27 (s, 2H), 6.80 (d, J=9 Hz, 4H), 6.89 (s,2H), 7.08 (d, J=9 Hz, 4H), 7.13 (d, J=5.1 Hz, 2H), 7.29 (d, J=5.1 Hz,2H).

Synthesis of the Compound IDTT

The compound 18 (1 g, 0.8 mmol) is placed in a 250 mL single-neckedflask, 100 mL of tetrahydrofuran and sulfuric acid (1 mL, 19 mmol) areadded thereinto for heating to 80° C. and incubating for 1 hr. Themixture is extracted with 100 mL of ether (×3) and 150 mL of pure water(×5), and the organic layer is collected and dried over MgSO₄. Theorganic solvent is removed by lowered pressure, and the residue ispurified by column chromatography on silica gel (ethyl acetate/hexanev/v=1/80 as eluent) to give a yellow solid IDTT (0.85 g, 88%). ¹H NMR(CDCl₃, 300 MHz, ppm): (t, J=6.9 Hz, 6H), 1.27-1.45 (m, 20H), 1.71-1.76(m, 4H), (t, J=6.6 Hz, 4H), 6.79 (d, J=8.7 Hz, 4H), 7.16 (d, J=8.7 Hz,4H), 7.24-7.28 (d, J=5.1 Hz, 2H), 7.46 (s, 2H).

Synthesis of the Compound Br-IDTT

The IDTT (1.1 g, 0.92 mmol) is placed in a single-necked flask anddissolved by adding 30 mL of tetrahydrofuran into the flask,N-bromosuccimide (0.38 g, 2.12 mmol) is further added into the flask,and the flask is wrapped with an aluminum foil to avoid the light. Thereaction is incubated at room temperature under nitrogen for 12 hrs andbeing terminated by adding water. The organic solvent is removed bylowered pressure, the residue is extracted with 50 mL of ether (×3) and50 mL of pure water, and the organic layer is collected and dried overMgSO₄. The organic solvent is removed by lowered pressure, and theresidue is purified by column chromatography on silica gel (hexane aseluent) to give a yellow solid Br-IDTT (1.08 g, 87%). ¹H NMR (CD2Cl2,300 MHz, ppm): (t, J=6.9 Hz, 6H), 1.26-1.40 (m, 20H), 1.67-1.76 (m, 4H),(t, J=6.6 Hz, 4H), 6.78 (d, J=8.7 Hz, 4H), 7.12 (d, J=8.7 Hz, 4H), 7.31(s, 2H), 7.24 (s, 2H), 7.47 (s, 2H).

Synthesis of the Compound Sn-IDTT

The Br-IDTT (0.85 g, 0.63 mmol) is placed in a 100 mL double-neckedflask to be baked under vacuum for three times, 30 mL of anhydroustetrahydrofuran is added thereinto, and the t-BuLi (2.5 M, 0.63 mL, 1.56mmol) is slowly dropped thereinto under −78° C. (by mixing the acetoneand the liquid nitrogen) for reacting for 30 min. The mixture isincubated at room temperature for 30 min and chlorotrimethylstannane(1.0 M, 1.9 mL, 1.89 mmol) is added into the mixture under −78° C., andthe mixture is returned to the room temperature for reacting 12 hrs. Thereaction is terminated by adding water, and the organic solvent isremoved under lowered pressure. The organic layer is collected byextracting with ether (50 mL×3) and pure water (50 mL), and thecollected organic layer is dried over MgSO₄. After removal of theorganic solvent under lowered pressure, hexane is used forre-crystallization and a pale yellow solid Sn-IDTT is obtained (0.52 g,54%). ¹H NMR (CDCl₃, 300 MHz, ppm): (s, 18H), (t, J=6.9 Hz, 6H),1.27-1.43 (m, 20H), 1.71-1.76 (m, 4H), (t, J=6.6 Hz, 4H), 6.79 (d, J=9Hz, 4H), 7.19 (d, J=9 Hz, 4H), 7.30 (s, 2H), 7.42 (s, 2H).

The synthetic processes of the polymers PIDTTBT and PIDTTDTBT areprovided as follows.

Synthesis of the Polymer PIDTTBT

The Sn-IDTT (160 mg, 0.11 mmol), the compound 7 (32.34 mg, 0.11 mmol),tris(dibenzylideneacetone)dipalladium (4.1 mg, 0.0044 mmol) andtri(2-methylphenyl)phosphine (10.72 mg, 0.035 mmol) are placed in a 50mL single-necked flask, and 7 mL of chlorobenzene pre-degassed withnitrogen is added into the flask. The mixture is degassed with nitrogenfor 10 min, and then the flask is equipped with a reflux condensor andbeing moved into a focused microwave synthesizer for microwavepolymerization under a condition of 270 watt at 180° C. for 50 min. Inturn, the end-capping 2-(tributylstannyl)thiophene (20.5 mg, 0.055 mmol)is added into the mixture for microwave polymerization under 270 watt at180° C. for 10 min, and 2-bromothiophene (9.78 mg, 0.06 mmol) is addedthereinto for reacting under the same condition. Then, 200 mL ofmethanol is used for re-precipitation and the solid is collected bygravity filtration. After the solid is continuously extracting with theacetone for one day, it is continuously extracting with hexane for oneday and resolved in the tetrahydrofuran. 5 eq. of Si-Thiol (19.01 mg,0.022 mmol) and a magnetic stirrer are added for demetalization for 12hr. After the Si-Thiol is filtered by gravity, the residue isre-recipitated by methanol. After filtration, the polymer PIDTTBT as adark blue solid is obtained (80 mg, 55%). Mn=19.0 kDa, PDI=1.47.

Synthesis of the Polymer PIDTTDTBT

The Sn-IDTT (100 mg, 0.066 mmol), the compound 5 (30.24 mg, 0.066 mmol),tris(dibenzylideneacetone)dipalladium (2.42 mg, 0.0026 mmol) andtri(2-methylphenyl)phosphine (6.43 mg, 0.021 mmol) are placed in a 50 mLsingle-necked flask, and 7 mL of chlorobenzene pre-degassed withnitrogen is added into the flask. The mixture is degassed with nitrogenfor 10 min, and the flask is equipped with a reflux condensor and thenbeing moved into a focused microwave synthesizer for microwavepolymerization under a condition of 270 watt at 180° C. for 50 min. Inturn, the end-capping 2-(tributylstannyl)thiophene (12.31 mg, 0.033mmol) is added into the mixture for microwave polymerization under 270watt at 180° C. for 10 min, and 2-bromothiophene (5.87 mg, 0.036 mmol)is added thereinto for reacting under the same condition. Then, 200 mLmethanol is used for re-precipitation and the solid is collected bygravity filtration. After the solid is continuously extracted with theacetone for one day, it is continuously extracted with hexane for oneday. The solid is resolved in the tetrahydrofuran, and 5 eq. of Si-Thiol(19.01 mg, 0.022 mmol) and a magnetic stirrer are added fordemetalization for 12 hr. After the Si-Thiol is filtered by gravity, theresidue is re-recipitated by methanol. After filtration, the polymerPIDTTDTBT as a dark black red solid is obtained (60 mg, 68%). Mn=26.5kDa, PDI=2.6.

The synthetic processes of the hexacyclic multielectron monomer B-DITTare provided as follows.

The Synthesis of the Compound 21

The compound 19 (5,5′-Bis(trimethylstannyl)thieno[2,3-d]dithiophene, 2g, 4.3 mmol) and the compound 20 (ethyl 2-bromobenzoate are placed in a100 mL double-necked flask, and the Pd(PPh₃)₄ (250 mg, 0.2 mmol) isadded into the double-necked flask in a glove box. After transferringthe double-necked flask outside the glove box, 43 mL of toluenepre-degassed by nitrogen is added into the flask. Under the nitrogen,the mixture is heated under 130° C. at reflux for 16 hrs, the organiclayer is removed by a rotary evaporator under lowered pressure. Then,the residue is purified by column chromatography on silica gel (ethylacetate/hexane v/v=20/1 as eluent) to quickly give a yellow solid, andthis solid is re-crystallized with the ethanol to give a yellow powder21 (1.65 g, 88%). ¹H NMR (CDCl₃, 300 MHz, ppm): (t, J=6.9 Hz, 6H),4.29-4.36 (q, J=7.2 Hz, 4H), 7.30 (d, J=5.4 Hz, 2H), 7.55 (d, J=5.4 Hz,2H), 7.52 (s, 2H), 8.21 (s, 2H).

Synthesis of the Compound 22

1.5 M Grignard Reagent Preparation:

The magnesium powder (2.23 g, 97.73 mmol) is placed in a 250 mLdouble-necked flask to be baked under vacuum for three times, 90 mL ofanhydrous tetrahydrofuran, 1-bromo-4-(octyloxy)benzene (26.10 g, 91.51mmol) and three drops of 1,2-dibromoethane are added thereinto, and themixture is incubated for 1 hr after being slightly heated. The compound21 (4.00 g, 9.16 mmol) is placed in a 500 mL double-necked flask to bebaked under vacuum for three times, 100 mL of anhydrous tetrahydrofuranis added thereinto under nitrogen, and 92 mL of freshly preparedGrignard reagent is added into this flask for being heated under 80° C.at reflux for 16 hrs. The mixture is extracted with 150 mL of ammoniumchloride, 150 mL of ether (×2) and 100 mL of pure water, and the organiclayer is collected and dried over MgSO₄. The organic solvent is removedby lowered pressure, and the residue is purified by columnchromatography on silica gel (dichloromethane/hexane v/v=1/10 as eluent)to give a yellow sticky 22 (7.5 g, 70%). ¹H NMR (CDCl₃, 300 MHz): 0.88(t, J=6.5 Hz, 12H), 1.20-1.50 (m, 40H), 1.78 (m, 8H), 3.42 (s, 2H), 3.95(t, J=6.5 Hz, 8H), 6.26 (s, 2H), 6.81 (d, J=9.0 Hz, 8H), 7.05 (d, J=9.0Hz, 8H), 7.19-7.35 (m, 8H).

Synthesis of the Compound DITT

The compound 22 (3.00 g, 2.56 mmol) is placed in a 250 mL single-neckedflask, 72 mL of acetic acid and a drop of sulfuric acid are addedthereinto for heating to 80° C. and incubating for 1 hr. The mixture isextracted with 100 mL of sodium bicarbonate (×2) and 50 mL of ethylacetate (×2), and the organic layer is collected and dried over MgSO₄.The organic solvent is removed by lowered pressure, and the residue ispurified by column chromatography on silica gel (dichloromethane/hexanev/v=1/20 as eluent) to give a yellowish brown solid DITT (2.16 g, 74%).¹H NMR (CDCl₃, 300 MHz): 0.87 (t, J=6.6 Hz, 12H), 1.20-1.55 (m, 40H),3.88 (t, J=6.5 Hz, 8H), 6.78 (d, J=8.9 Hz, 8H), 7.16 (d, J=8.9 Hz, 8H),7.20-7.30 (m, 4H), 7.35 (d, J=7.8 Hz, 2H), 7.38 (d, J=7.8 Hz, 2H).

Synthesis of the Compound Br-DITT

The DITT (0.50 g, 0.44 mmol) is placed in a 50 mL double-necked flask,15.4 mL of chloroform is poured thereinto, and 9.3 mg of ferrictrichloride is added into the flask under room temperature for reactingfor 12 hrs. The reaction is terminated by adding water, the organicsolvent is removed by lowered pressure, the residue is extracted with 50mL of ether (×3) and 50 mL of pure water, and the organic layer iscollected and dried over MgSO₄. The organic solvent is removed bylowered pressure, and the hexane is used for recrystallization to give apale yellow solid Br-DITT (0.55 g, 97%). ¹H NMR (CDCl₃, 300 MHz): 0.87(t, J=6.3 Hz, 12H), 1.20-1.50 (m, 40H), 1.74 (m, 8H), 3.89 (t, J=6.5 Hz,8H), 6.80 (d, J=9.0 Hz, 8H), 7.12 (d, J=9.0 Hz, 8H), 7.20 (d, J=8.1 Hz,2H), 7.39 (d, J=8.1 Hz, 2H), 7.48 (s, 2H).

Synthesis of the Compound B-DITT

The Br-DITT (1.00 g, 0.77 mmol) is placed in a 100 mL double-neckedflask to be baked under vacuum for three times, 27 mL of anhydroustetrahydrofuran is added thereinto, and the t-BuLi (2.5 M, 1 mL, 2.44mmol) is slowly dropped thereinto under −78° C. (by mixing the acetoneand the liquid nitrogen) for reacting for 1 hr. The mixture is incubatedat room temperature for 20 min and the boron ester reagent(2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, 0.58 M, 3.12mmol) is added into the mixture under −78° C., and the mixture isreturned to the room temperature for reacting 12 hrs. The reaction isterminated by adding water, and the organic solvent is removed underlowered pressure. The organic layer is collected by extracting withether (150 mL×3) and pure water (50 mL), and the collected organic layeris dried over MgSO₄. After removal of the organic solvent under loweredpressure, hexane is used for re-crystallization and a pale yellow solidB-DITT is obtained (0.57 g, 53%). ¹H NMR (CDCl₃, 300 MHz): 0.86 (t,J=5.9 Hz, 12H), 1.20-1.1.40 (m, 40H), 1.72 (m, 64H), 3.88 (t, J=6.5 Hz,8H), 6.77 (d, J=8.6 Hz, 8H), 7.16 (d, J=8.6 Hz, 8H), 7.34 (d, J=7.5 Hz,2H), 7.73 (d, J=7.5 Hz, 2H), 7.78 (s, 2H).

The synthetic processes of the polymers PDITTBT and PDITTDTBT areprovided as follows.

Synthesis of the Polymer PDITTBT

The B-DITT (216.8 mg, 0.16 mmol), the compound 7 (46 mg, 0.16 mmol),Pd(PPh₃)₄ (3.6 mg, 0.0031 mmol), K₂CO₃ (163.3 mg, 1.18 mmol) and Aliquat336 (27 mg, 0.07 mmol) are placed in a 25 mL single-necked flask, and 5mL of toluene pre-degassed with nitrogen and 1 mL of distilled water arepoured into the flask. The mixture is degassed with nitrogen for 10 min,and then the flask is equipped with a reflux condensor forpolymerization at 90° C. for 72 hrs. Then, 400 mL of methanol is usedfor re-precipitation and the solid is collected by gravity filtration.After the solid is continuously extracting with the acetone for one day,it is continuously extracting with hexane for one day and resolved inthe tetrahydrofuran. 4 eq. of Si-Thiol (10.8 mg, 0.64 mmol) and amagnetic stirrer are added for demetalization for 12 hr. After theSi-Thiol is filtered by gravity, the residue is re-recipitated bymethanol. After filtration, the polymer PDITTBT as a black green solidis obtained (103 mg, 52%). Mn=19.0 kDa, PDI=1.76.

Synthesis of the Polymer PDITTDTBTBT

The B-DITT (216.8 mg, 0.16 mmol), the compound 5 (71.5 mg, 0.16 mmol),Pd(PPh₃)₄ (3.6 mg, 0.0031 mmol), K₂CO₃ (163.3 mg, 1.18 mmol) and Aliquat336 (27 mg, 0.07 mmol) are placed in a 25 mL single-necked flask, and 5mL of toluene pre-degassed with nitrogen and 1 mL of distilled water arepoured into the flask. The mixture is degassed with nitrogen for 10 min,and then the flask is equipped with a reflux condensor forpolymerization at 90° C. for 72 hrs. Then, 400 mL of methanol is usedfor re-precipitation and the solid is collected by gravity filtration.After the solid is continuously extracting with the acetone for one day,it is continuously extracting with hexane for one day and resolved inthe tetrahydrofuran. 4 eq. of Si-Thiol (10.8 mg, 0.64 mmol) and amagnetic stirrer are added for demetalization for 12 hr. After theSi-Thiol is filtered by gravity, the residue is re-recipitated bymethanol. After filtration, the polymer PDITTDTBTBT as a black greensolid is obtained (130 mg, 58%). Mn=8.1 kDa, PDI=2.1.

The synthetic processes of the nonacyclic multielectron monomer Sn-TPTPTare provided as follows.

Synthesis of the Compound B-DIDT

The Br-DITT (1.06 g, 1.22 mmol) dissolved in 28 mL of anhydroustetrahydrofuran is placed in a 100 mL double-necked flask and 2.8 Mt-BuLi (1.6 mL in hexane, 3.91 mmol) is slowly dropped thereinto under−78° C. After stirring the mixture under −78° C. for 2 hrs,2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (0.91 g, 4.89 mmol)is slowly dropped into the reacting flask and the mixing solution isreturned to the room temperature and stirred for 16 hrs continuously.The mixture is extracted with ethyl acetate (300 mL×3) and pure water(150 mL), and the water in the organic layer is removed by the anhydrousMgSO₄. The residue is concentrated by rotation, purified by columnchromatography on silica gel (hexane/ethyl acetate v/v=40/1 as eluent),and re-crystallized by the methanol to give a yellow solid B-DIDT (0.85g, 72%). ¹H NMR (CDCl₃, 300 MHz): 7.74 (d, J=7.4 Hz, 2H), 7.60 (s, 2H),7.37 (d, J=7.4 Hz, 2H), 1.98-2.18 (m, 8H), 1.39 (s, 12H), 0.50-1.30 (m,60H).

Synthesis of the Compound 24

B-DIDT (2.20 g, 2.29 mmol), ethyl 2-bromothiophene-3-carboxylate (1.24g, 5.27 mmol), Pd(PPh₃)₄ (0.265 g, 0.23 mmol), K2CO3 (1.90 g, 13.75mmol), and Aliquant 336 (0.23 g, 0.57 mmol) in a solution of degassedtoluene (17 mL) and degassed H2O (3.5 mL) are introduced to a 50 mLround-bottom flask. The reaction solution is heated to 90° C. andcontinuously stirred for 72 hrs. The reaction solution is extracted withethyl acetate (300 mL×3) and water (150 mL). The combined organic layerwas dried over MgSO4. The residue is purified by column chromatographyon silica gel (hexane/ethyl acetate, v/v, 20/1) and then recrystallizedfrom hexane to give a light yellow solid 24 (2.07 g, 62%). ¹H NMR(CDCl₃, 300 MHz): δ 7.52 (d, J=5.6 Hz, 2H), 7.51-7.30 (m, 6H), 3.17-3.58(m, 4H), 7.23 (d, J=5.6 Hz, 2H), 4.20 (q, J=7.2 Hz, 4H), 2.09 (t, J=8.1Hz, 8H), 1.40-0.96 (m, 54H), 0.82 (t, J=13.4 Hz, 12H).

Synthesis of the Compound 25

A Grignard reagent is prepared by the following procedure. The magnesiumturnings (0.8 g, 33.3 mmol) is placed in a 50 mL double-necked flask tobe baked under vacuum for three times, 20 mL of anhydroustetrahydrofuran and 3-4 drops of 1,2-dibromoethane are added thereinto,and 1-bromo-4-(octyloxy)benzene (8.56 g, 30.0 mmol) is slowly addedthereinto for evenly stirring 1 h. The compound 24 (0.80 g, 0.79 mmol)is placed in a 100 mL double-necked flask, 20 mL anhydroustetrahydrofuran is added thereinto for evenly stirring and mixing, andfreshly prepared 4-(octyloxy)benzene 1-magnesium bromide (20 mL, 7.9mmol) is added thereinto dropwise at room temperature. The resultingmixture is heated under 80° C. at reflux and continuously stirred for 16hrs. The reaction solution is extracted with ethyl acetate (150 mL×3)and water (100 mL). The combined organic layer is dried over MgSO4. Theresidue is purified by column chromatography on silica gel (hexane/ethylacetate, v/v, 100/1) to give a yellow oil 25 (1.17 g, 85%). ¹H NMR(CDCl₃, 300 MHz): δ 7.24 (d, J=9.0 Hz, 2H), 7.17 (d, J=9.0 Hz, 2H), 7.16(d, J=9.0 Hz, 8H), 7.09 (d, J=5.1 Hz, 2H), 6.94 (s, 2H), 6.84 (d, J=9.0Hz, 8H), 6.41 (d, J=5.6 Hz, 2H), 3.97 (t, J=6.5 Hz, 8H), 3.07 (s, 2H),1.95-1.60 (m, 16H), 1.55-0.40 (m, 112H).

The Synthesis of the Compound TPTPT

The compound 25 (2.00 g, 1.14 mmol) is placed in a 250 mL double-neckedflask, 116 mL of acetic acid is added for heating and dissolving thecompound 25, and 3.5 mL of conc. sulfuric acid is slowly droppedthereinto. The resulting solution is stirred for 18 h at 95° C. and thenis extracted with ethyl acetate (500 mL×3) and water (250 mL). Thecombined organic layer is dried over MgSO4. The residue is purified bycolumn chromatography on silica gel (hexane/ethyl acetate, v/v, 100/1)to give an orange oil TPTPT (1.58 g, 81%). ¹H NMR (d8-THF, 300 MHz): δ7.45 (s, 2H), 7.34 (d, J=4.8 Hz, 2H), 7.33 (s, 2H), 7.12 (d, J=8.7 Hz,8H), 6.99 (d, J=4.8 Hz, 2H), 6.72 (d, J=8.7 Hz, 8H), 3.87 (t, J=6.0 Hz,8H), 2.3-2.1 (m, 8H), 1.50-0.95 (m, 96H), 0.90-0.70 (m, 24H).

Synthesis of the Compound Br-TPTPT

TPTPT (1.58 g, 0.92 mmol) in chloroform (87 mL) is placed in a 250 mLdouble-necked flask, N-bromosuccinimide (0.36 g, 2.23 mmol) is addedthereinto at room temperature. The flask is wrapped with the alumiunmfoil and stirred for 12 h at room temperature and then is quenched bywater (100 mL). The mixture solution is extracted with chloroform (450mL×3) and water (150 mL). The combined organic layer is dried overMgSO4. After removal of the solvent under lowered pressure, the residueis purified by column chromatography on silica gel (hexane/ethylacetate, v/v, 100/1) and then recrystallized from hexane to give anorange solid Br-TPTPT (1.12 g, 65%). ¹HNMR (CDCl₃, 300 MHz): 7.23 (s,2H), 7.18 (s, 2H), 7.12 (d, J=8.7 Hz, 8H), 6.99 (s, 2H), 6.78 (d, J=8.7Hz, 8H), 3.90 (t, J=6.5 Hz, 8H), 2.07 (t, J=8.0 Hz, 8H), 1.80-1.70 (m,8H), 1.50-0.60 (m, 112H).

TPTPT (1.60 g, 0.93 mmol) is placed in a 50 mL double-necked flask, and28 mL of anhydrous tetrahydrofuran is added thereinto foe evenlystirring and dissolving the TPTPT. 1.6 M t-BuLi in hexane (1.8 mL, 2.80mmol) is dropwise added into the flask at −78° C. After stirring at −78°C. for 1 h, 1.0 M solution of chlorotrimethylstannane in THF (3.7 mL,3.73 mmol) is introduced dropwise by syringe to the solution. Themixture solution is quenched with water and extracted with Chloroform(450 mL×3) and water (150 mL). The combined organic layer is dried overMgSO4. After removal of the solvent by a rotary evaporator, Sn-TPTPT(1.18 g, 62%) is obtained as an orange oil and used without furtherpurification. ¹H NMR (CDCl₃, 300 MHz): δ 7.29 (s, 2H), 7.27 (s, 2H),7.21 (d, J=8.7 Hz, 8H), 7.06 (s, 2H), 6.81 (d, J=8.7 Hz, 8H), 3.94 (t,J=6.3 Hz, 8H), 2.20-2.00 (m, 8H), 1.85-1.70 (m, 8H), 1.50-0.60 (m,112H), 0.40 (s, 18H).

The synthetic processes of the polymer PTPTPTBT are provided as follows.

Synthesis of the Polymer PTPTPTBT

Sn-TPTPT (143.0 mg, 0.07 mmol), 7 (20.6 mg, 0.07 mmol) Pd(PPh₃)₄ (3.2mg, 0.0035 mmol), tri(o-tolyl)phosphine (6.8 mg, 0.022 mmol) and 3 mL ofanhydrous chlorobenzene are placed in a round bottom flask. The mixingsolution is degassed with nitrogen for 10 min at the room temperature,and the flask is moved into a microwave reactor under a condition of 270watt for 45 min. Then, the tributyl(thiophen-2-yl)stannane (13.1 mg,0.035 mmol) is added in to the flask under 270 watt for 10 min. Finally,2-bromothiophene (6.2 mg, 0.038 mmol) is added in to the flask under 270watt for 10 min. The mixture is dropwise added into the methanol forre-precipitation, the solid is collected by filtration, and the filtrateis continuously extracted with the acetone, the hexane and thechloroform. The Pd-thiol gel (Silicycle Inc.) and Pd-TAAcOH are addedinto the chloroform solution for removing the remaining catalyst Pd andthe metal Sn. After the gel is removed by filtrationan the solvent isremoved by a rotary evaporator, the polymer is re-dissolved in a smallamount of chloroform and re-precipitated by the methanol. The purifiedpolymer is collected by filtration and dried under vacuum to give thePTPTPTBT as a dark green strip solid (215 mg, 62%). Mn=30000, PDI=1.69.¹H NMR (CDCl₃, 300 MHz): 8.20-8.00 (m, 2H), 7.95-7.80 (m, 2H), 7.50-7.30(m, 4H), 7.25-7.15 (m, 8H), 6.90-6.70 (m, 8H), 4.00-3.80 (m, 8H),1.85-1.60 (m, 16H), 1.50-1.00 (m, 88H), 0.90-0.70 (m, 24H).

Through the above embodiments, it is known that the present inventionprovides the chemical structures of various ladder-type multifusedarenes and the synthetic methods thereof, and also provides the p-typelow bandgap conjugated copolymers by hybriding the ladder-typemultifused arenes and the electron deficient acceptor and the syntheticmethod thereof. Specifically, the present invention is based on variousladder-type multifused arenes. By various cyclizations, one or morearomatic ring and/or one or more heteroring such as thiophene, pyrrole,carbazole, fluorine, silole or cyclopentadiene are formed on theladder-type multifused arenes to design and synthesize the hexacyclic,heptacyclic and nonacyclic units multifused arenes. For example, thepresent invention provides a method of synthesizing a monomer, includingsteps of providing a compound having a structure being one of

wherein R is a side chain at least including a carbon atom, andperforming an annulation with the compound to cause the compound to formthe monomer.

Besides, the present invention also links the conjugated small moleculesof the ladder-type multifused arenes and that of the various electrondeficient monomer/electron acceptor to form a p-type conjugated polymer.For example, the present invention also provides a method ofsynthesizing a p-type conjugated polymer, including steps of providing acompound having a structure being one of

wherein R is a side chain at least including a carbon atom, forming atleast one aromatic ring on the compound for form a monomer, andpolymerizing the monomer and an electron acceptor to form the p-typeconjugated polymer.

Further, the above electron acceptor/electron deficient monomer is oneselected from a group consisting of:

For example, the p-type conjugated polymer is preferably synthesized asa method including the steps of providing a compound

linking the thiophenes on both sides to the tricyclic system by asilicon atom respectively, modifying with an appropriate R group andproviding a electron acceptor

After polymerization, a ladder type heptacyclic multifused p-typeconjugated polymer with a novel structure

is formed, which maintains the same conjugated backbone but has anenhanced molecular planarity. It is proved that this ladder typeheptacyclic multifused p-type conjugated polymer has a good opticalabsorption and electron hole transporting properties.

The side chain R in the above embodiments preferably has any length andsize. Specifically, the side chain having at least one carbon atom ispreferably be used in the side chain R as described in the presentinvention.

The p-type conjugated polymers is preferably blended with the n-typematerial such as C₇₀ derivative [6,6]-phenyl C₇₁-butyric acid methylester (PC₇₁BM) or C₆₀ derivative [6,6]-phenyl C₆₁-butyric acid methylester (PC₆₁BM) in various organic solvents and then spin-coated to serveas the active layer of the organic doped solar cell for achieving a highefficiency organic solar cell with a multi-layer structure.

The following Table 1 illustrates the respective optoelectronicproperties of the elements in the active layer of the organic solar cellmade by several p-type conjugated polymers of the present inventionblending with PC₇₁BM.

TABLE 1 Power Blend Open Short conversion ratio circuit circuit Fillefficiency Conjugated with voltage current factor (PCE, polymer PC₇₁BM(V) (mA/cm²) (%) %) PDTSCBT 1:3 0.82 11.1 56.7 5.2 PDTPCBT 1:2 0.50 10.549.9 2.6 PDTBCDTBT 1:1.5 0.78 11.4 65.6 5.9 PDTCFBT 1:3 0.83 12.6 66.87.0 PBBCPDTTPD 1:2.5 0.85 11.7 51.7 5.2 PBBCPDTBT 1:2.5 0.75 12.5 51.64.8 PBBCPDTBT-F 1:2.5 0.85 11.9 56.9 5.8 PIDTTBT 1:4 0.82 10.5 46.0 4.0PIDTTDTBT 1:4 0.82 8.9 49.0 3.6 PDITTDTBT 1:4 0.92 10.7 58.4 5.8 PDITTBT1:4 0.88 7.5 41.4 2.7 PTPTPTBT 1:4 0.76 11.4 61.0 5.3

Through the Table 1, it is known that the active layer elements made ofthe p-type conjugated polymers of the present invention blending withn-type material have good properties of high short circuit current andhigh PCE. Detailedly speaking, the multifused p-type conjugated polymerof the present invention is preferably applied to the organic blendsolar cell having a multilayer structure, which is spin-coated on thePEDOT:PSS as an active layer by blending with the n-type material. Thep-type material has the following properties. 1) It elongates effectiveconjugation length, 2) facilitates π-electron delocalization, 3) reducesthe band gap, and 4) suppresses the rotational disorder aroundinterannular single bounds to lower the reorganization energy and beingbeneficial for intrinsic charge mobility by the planar and rigidstructure.

The present application enhances the scope and the intensity of thesunlight spectrum absorbed by the active layer by introducing a novelmultifused p-type conjugated polymer into the active layer of theorganic blend solar cell, and increases the hole transporting ability bythe coplanar and rigid structure of the p-type conjugated polymeritself. Thereby, the short circuit current of the organic blend solarcell is enhanced and the re-combination probability of the electron holeis decreased to achieve a high efficiency organic solar cell with amultilayer structure.

Specifically, the present invention is further described by thefollowing exemplary embodiments.

1. A polymer, having a structure being one selected from a groupconsisting of:

wherein A is an electron-deficient monomer, n is an integer larger than2 and R is a side chain at least including a carbon atom.

2. According to example 1, wherein the electron-deficient monomer is oneselected from a group consisting of

and R on the electron-deficient monomer is a side chain at leastincluding a carbon atom.

3. A polymer material, comprising:

-   -   a plurality of monomers, wherein the plurality of monomers are        one selected from a group consisting of

wherein R is a side chain at least including a carbon atom.

4. A polymer monomer having a structure being one selected from a groupconsisting of:

wherein R is a side chain at least including a carbon atom.

5. A method of synthesizing a monomer, including steps of:

-   -   providing a compound having a structure being one of

wherein R is a side chain at least including a carbon atom; and

-   -   performing an annulation with the compound to cause the compound        to form the monomer.

6. According to example 5, wherein the annulation synthesizes at leastone aromatic ring on the compound.

7. A method of synthesizing a polymer, including steps of:

-   -   providing a compound having a structure being one of

wherein R is a side chain at least including a carbon atom;

-   -   forming at least one aromatic ring on the compound to form a        monomer; and    -   polymerizing the monomer and an electron acceptor to form a        polymer.

8 According to example 7, wherein the aromatic ring is a heterocycle.

9. A method of synthesizing a polymer, including steps of:

-   -   providing a monomer, wherein the monomer is one selected from a        group consisting of:

10. According to example 9, wherein the electron acceptor is oneselected from a group consisting of:

-   -   and R on the electron acceptor is a side chain at least        including a carbon atom.

While the present invention has been detailedly described with referenceto the above embodiments, it will be understood by those skilled in theart that various modifications and variations may be made thereinwithout departing from the scope of the present invention as defined bythe appended claims.

REFERENCES

-   1. Chiu-Hsiang Chen, Yen-Ju Cheng, Chih-Yu Chang, and Chain-Shu Hsu.    Donor-Acceptor Random Copolymers Based on a Ladder-Type Nonacyclic    Unit Synthesis, Characterization, and Photovoltaic Applications.    Macromolecules. 2011 44 (21), 8415-8424.-   2. Yen-Ju Cheng, Chiu-Hsiang Chen, Yu-Shun Lin, Chih-Yu Chang, and    Chain-Shu Hsu. Ladder-Type Nonacyclic Structure Consisting of    Alternate Thiophene and Benzene Units for Efficient Conventional and    Inverted Organic Photovoltaics. Chemistry of Materials. 2011 23    (22), 5068-5075.-   3. Chih-Yu Chang, Yen-Ju Cheng, Shih-Hsiu Hung, Jhong-Sian Wu,    Wei-Shun Kao, Chia-Hao Lee, Chain-Shu Hsu. Combination of Molecular,    Morphological, and Interfacial Engineering to Achieve Highly    Efficient and Stable Plastic Solar Cells. Adv. Mater 2012, 24, No.    04, 549-553.-   4. Jhong-Sian Wu, Yen-Ju Cheng, Tai-Yen Lin, Chih-Yu Chang, Peng-I.    Shih, and Chain-Shu Hsu. Dithienocarbazole-Based Ladder-Type    Heptacyclic Arenes with Silicon, Carbon, and Nitrogen Bridges:    Synthesis, Molecular Properties, Field-Effect Transistors, and    Photovoltaic Applications. Adv. Funct. Mater 2012, 22(8), 1711-1722.-   5. Yen-Ju Cheng, Sheng-Wen Cheng, Chih-Yu Chang, Wei-Shun Kao,    Ming-Hung Liao and Chain-Shu Hsu. Diindenothieno[2,3-b]thiophene    arene for efficient organic photovoltaics with an extra high    open-circuit voltage of 1.14 ev. Chem. Commun., 2012, 48, 3203-3205.

What is claimed is:
 1. A polymer, having a structure being one selectedfrom a group consisting of:

wherein A is an electron-deficient monomer, n is an integer larger than2 and R is a side chain at least comprising a carbon atom.
 2. A polymeras claimed in claim 1, wherein the electron-deficient monomer is oneselected from a group consisting of

and R on the electron-deficient monomer is a side chain at leastcomprising a carbon atom.
 3. A polymer monomer having a structure beingone selected from a group consisting of:

wherein R is a side chain at least comprising a carbon atom.
 4. Apolymer monomer as claimed in claim 3, wherein the polymer monomer ispolymerized as a polymer material.
 5. A method of synthesizing amonomer, comprising steps of: providing a compound having a structurebeing one of

wherein R is a side chain at least comprising a carbon atom; andperforming an annulation with the compound to cause the compound to formthe monomer.
 6. A method as claimed in claim 5, wherein the annulationsynthesizes at least one aromatic ring on the compound.
 7. A method asclaimed in claim 6, wherein the aromatic ring is a heterocycle.
 8. Amethod as claimed in claim 5, further comprising a step of: polymerizingthe monomer and an electron acceptor to form a polymer.
 9. A method asclaimed in claim 5, wherein the monomer is one selected from a groupconsisting of:


10. A method as claimed in claim 8, wherein the electron acceptor is oneselected from a group consisting of:

and R on the electron acceptor is a side chain at least comprising acarbon atom.